His literary labors have had an almost incredible extent and variety.  He Himself gives the following enumeration of his writings:  “In Dutch I have written:  a History of our Mission and of distinguished Missionaries, and an appeal for support of the Missionary Work; in German:  Sketches of the Minor Prophets; in Latin:  The Life of our Savior; in English:  Sketches of Chinese History; China Opened; Life of Kanghe, together with a great number of articles on the Religion, History, Philosophy, Literature and Laws of the Chinese; in Siamese:  a Translation of the New Testament, with the Psalms, and an English-Siamese Dictionary, English-Cambodian Dictionary and English-Laos Dictionary.  These works I left to my successors to finish, but with the exception of the Siamese Dictionary they have added nothing to them.  In Cochin-Chinese:  a Complete Dictionary Cochin-Chinese-English and English-Cochin-Chinese; this work is not yet printed.  In Chinese:  Forty Tracts, along with three editions of the Life of our Savior; a Translation of the New Testament, the third edition of which I have carried through the press.  Of the Translations of the Old Testament the Prophets and the two first books of Moses are completed.  In this language I have also written The Chinese Scientific Monthly Review, a History of England, a History of the Jews, a Universal History and Geography, on Commerce, a short Account of the British Empire and its Inhabitants, as well as a number of smaller articles.  In Japanese:  a Translation of the New Testament, and of the first book of Moses, two tracts, and several scientific pamphlets.  The only paper to which I now send communications is the Hong Kong Gazette, the whole Chinese department of which I have undertaken.  Till the year 1842 I wrote for the Chinese Archives.”

The writer in the Grenzboten goes on to say that “so vast a surface as these writings cover, requires a surprising facility of mind and an indefatigable perseverance.  When you see the man engaged in his missionary toils you understand the whole at once.  He arrives in a city and hastens to the church which is prepared for his reception.  After preaching for an hour with the greatest energy he takes up his collection and is gone.  He speaks with such rapidity that it is hardly possible to follow him.  Such rapidity is not favorable to excellence in the work.  Of all his writings, only one work is known to me, that published in Munich, in 1847, under the title of ’Gutzlaffs History of the Chinese Empire from the earnest times to the Peace of Nankin’.  In our imperfect acquaintance with Chinese history this compendium is not without value, but it displays no critical power, and is a mere external compilation and poorly written.  From it we learn as good as nothing of the peculiar customs and state of mental culture of the country.  The whole resembles a Christian History of the World written in the eighteenth century, Beginning with Adam and Eve, and leaving the Greeks and Romans out altogether because they were without a divine revelation.”